As a large-size projection type image display apparatus having a large display screen, there is known a projection type image display apparatus in which an image(s) reflected on an image display element such as a transmission type liquid crystal panel or reflection type liquid crystal panel is projected on a screen as a projection surface by a projection lens.
In recent years, there has prevailed a projection type image display apparatuses using so-called short-projection-distance projection lenses in which a distance from a screen to such an apparatus is short. For example, Patent Document 1 discloses an apparatus that includes an projection lens having: a first optical system with a transmission type refractive element; and a second optical system with a reflection type refractive element and in which some lenses of the first optical system is housed in a lower space (dead space) whose lower limit is defined by a lower end of the second optical system. In addition, Patent Document 2 discloses that a projection optical system can project a high-quality projection image onto a large screen by combining a lens system and a concave mirror even if its entire length is short.